/*!	 valuenode_derivative.cpp
**	 Implementation of the "Derivative" valuenode conversion.
**
**	Copyright (c) 2014 Carlos López
**
**	This package is free software; you can redistribute it and/or
**	modify it under the terms of the GNU General Public License as
**	published by the Free Software Foundation; either version 2 of
**	the License, or (at your option) any later version.
**
**	This package is distributed in the hope that it will be useful,
**	but WITHOUT ANY WARRANTY; without even the implied warranty of
**	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
**	General Public License for more details.
**
*/

#ifdef USING_PCH
#	include "pch.h"
#else
#ifdef HAVE_CONFIG_H
#	include <config.h>
#endif

#include "valuenode_derivative.h"
#include "valuenode_const.h"
#include <synfig/general.h>
#include <synfig/localization.h>
#include <synfig/valuenode_registry.h>
#include <ETL/misc>

#endif

using namespace std;
using namespace etl;
using namespace synfig;

// E= EVALUATE
#define E(x,t,y) ( (*x)(t).get(y) )
// D= DERIVATIVE
// See http:// en.wikipedia.org/wiki/Finite_difference_coefficients#Central_finite_difference
// First Derivatives
#define D_ROUGH(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-h,y)*(-1.0/2.0)+      \
				E(x,t+h,y)*( 1.0/2.0)       \
				)/(h)                       \
				)
#define D_NORMAL(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-2*h,y)*( 1.0/12.0)+   \
				E(x,t-h  ,y)*( -2.0/3.0)+   \
				E(x,t+h  ,y)*(  2.0/3.0)+   \
				E(x,t+2*h,y)*(-1.0/12.0)    \
				)/(h)                       \
				)
#define D_FINE(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-3*h,y)*(-1.0/60.0)+   \
				E(x,t-2*h,y)*( 3.0/20.0)+   \
				E(x,t-h  ,y)*( -3.0/4.0)+   \
				E(x,t+h  ,y)*(  3.0/4.0)+   \
				E(x,t+2*h,y)*(-3.0/20.0)+   \
				E(x,t+3*h,y)*( 1.0/60.0)    \
				)/(h)                       \
				)
#define D_EXTREME(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-4*h,y)*( 1.0/280.0)+  \
				E(x,t-3*h,y)*(  -4.0/105)+  \
				E(x,t-2*h,y)*(   1.0/5.0)+  \
				E(x,t-h  ,y)*(  -4.0/5.0)+  \
				E(x,t+h  ,y)*(   4.0/5.0)+  \
				E(x,t+2*h,y)*(  -1.0/5.0)+  \
				E(x,t+3*h,y)*( 4.0/105.0)+  \
				E(x,t+4*h,y)*(-1.0/280.0)   \
				)/(h)                       \
				)

// Second Derivatives
#define DD_ROUGH(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-h,y)*( 1.0)+          \
				E(x,t,y  )*(-2.0)+          \
				E(x,t+h,y)*( 1.0)           \
				)/(h*h)                     \
				)
#define DD_NORMAL(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-2*h,y)*(-1.0/12.0)+   \
				E(x,t-h  ,y)*(  4.0/3.0)+   \
				E(x,t    ,y)*( -5.0/2.0)+   \
				E(x,t+h  ,y)*(  4.0/3.0)+   \
				E(x,t+2*h,y)*(-1.0/12.0)    \
				)/(h*h)                     \
				)
#define DD_FINE(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-3*h,y)*(  1.0/90.0)+  \
				E(x,t-2*h,y)*( -3.0/20.0)+  \
				E(x,t-h  ,y)*(   3.0/2.0)+  \
				E(x,t    ,y)*(-49.0/18.0)+  \
				E(x,t+h  ,y)*(   3.0/2.0)+  \
				E(x,t+2*h,y)*( -3.0/20.0)+  \
				E(x,t+3*h,y)*(  1.0/90.0)   \
				)/(h*h)                     \
				)
#define DD_EXTREME(x,t,h,y)\
				(                           \
				(                           \
				E(x,t-4*h,y)*( -1.0/560.0)+ \
				E(x,t-3*h,y)*(  8.0/315.0)+ \
				E(x,t-2*h,y)*(   -1.0/5.0)+ \
				E(x,t-h  ,y)*(    8.0/5.0)+ \
				E(x,t    ,y)*(-205.0/72.0)+ \
				E(x,t+h  ,y)*(    8.0/5.0)+ \
				E(x,t+2*h,y)*(   -1.0/5.0)+ \
				E(x,t+3*h,y)*(  8.0/315.0)+ \
				E(x,t+4*h,y)*( -1.0/560.0)  \
				)/(h*h)                     \
				)

REGISTER_VALUENODE(ValueNode_Derivative, RELEASE_VERSION_1_0, "derivative", "Derivative")

ValueNode_Derivative::ValueNode_Derivative(const ValueBase &value):
    LinkableValueNode(value.get_type())
{
    Vocab ret(get_children_vocab());
    set_children_vocab(ret);
    set_link("interval",      ValueNode_Const::create(Real(0.01))); // Default interval
    set_link("accuracy",      ValueNode_Const::create((int)(NORMAL)));
    set_link("order",         ValueNode_Const::create((int)(FIRST)));

    Type &type(get_type());

    if (type == type_real) {
        set_link("link", ValueNode_Const::create(value.get(Real())));
    } else if (type == type_time) {
        set_link("link", ValueNode_Const::create(value.get(Time())));
    } else if (type == type_angle) {
        set_link("link", ValueNode_Const::create(value.get(Angle())));
    } else if (type == type_vector) {
        set_link("link", ValueNode_Const::create(value.get(Vector())));
    } else {
        throw Exception::BadType(type.description.local_name);
    }
}

LinkableValueNode*
ValueNode_Derivative::create_new()const
{
    return new ValueNode_Derivative(get_type());
}

ValueNode_Derivative*
ValueNode_Derivative::create(const ValueBase &x)
{
    return new ValueNode_Derivative(x);
}

ValueNode_Derivative::~ValueNode_Derivative()
{
    unlink_all();
}

ValueBase
ValueNode_Derivative::operator()(Time t)const
{
    if (getenv("SYNFIG_DEBUG_VALUENODE_OPERATORS")) {
        printf("%s:%d operator()\n", __FILE__, __LINE__);
    }

    Type &type(get_type());

    if (type == type_real) {
        switch ((*accuracy_)(t).get(int())) {
        case ROUGH:
            return (*order_)(t).get(int()) ?
                   DD_ROUGH(link_, t, (*interval_)(t).get(Real()), Real()) :
                   D_ROUGH(link_, t, (*interval_)(t).get(Real()), Real());
            break;

        case FINE:
            return (*order_)(t).get(int()) ?
                   DD_FINE(link_, t, (*interval_)(t).get(Real()), Real()) :
                   D_FINE(link_, t, (*interval_)(t).get(Real()), Real());
            break;

        case EXTREME:
            return (*order_)(t).get(int()) ?
                   DD_EXTREME(link_, t, (*interval_)(t).get(Real()), Real()) :
                   D_EXTREME(link_, t, (*interval_)(t).get(Real()), Real());
            break;

        case NORMAL:
        default:
            return (*order_)(t).get(int()) ?
                   DD_NORMAL(link_, t, (*interval_)(t).get(Real()), Real()) :
                   D_NORMAL(link_, t, (*interval_)(t).get(Real()), Real());
            break;
        }
    } else if (type == type_time) {
        switch ((*accuracy_)(t).get(int())) {
        case ROUGH:
            return (*order_)(t).get(int()) ?
                   DD_ROUGH(link_, t, (*interval_)(t).get(Real()), Time()) :
                   D_ROUGH(link_, t, (*interval_)(t).get(Real()), Time());
            break;

        case FINE:
            return (*order_)(t).get(int()) ?
                   DD_FINE(link_, t, (*interval_)(t).get(Real()), Time()) :
                   D_FINE(link_, t, (*interval_)(t).get(Real()), Time());
            break;

        case EXTREME:
            return (*order_)(t).get(int()) ?
                   DD_EXTREME(link_, t, (*interval_)(t).get(Real()), Time()) :
                   D_EXTREME(link_, t, (*interval_)(t).get(Real()), Time());
            break;

        case NORMAL:
        default:
            return (*order_)(t).get(int()) ?
                   DD_NORMAL(link_, t, (*interval_)(t).get(Real()), Time()) :
                   D_NORMAL(link_, t, (*interval_)(t).get(Real()), Time());
            break;
        }
    } else if (type == type_angle) {
        switch ((*accuracy_)(t).get(int())) {
        case ROUGH:
            return (*order_)(t).get(int()) ?
                   DD_ROUGH(link_, t, (*interval_)(t).get(Real()), Angle()) :
                   D_ROUGH(link_, t, (*interval_)(t).get(Real()), Angle());
            break;

        case FINE:
            return (*order_)(t).get(int()) ?
                   DD_FINE(link_, t, (*interval_)(t).get(Real()), Angle()) :
                   D_FINE(link_, t, (*interval_)(t).get(Real()), Angle());
            break;

        case EXTREME:
            return (*order_)(t).get(int()) ?
                   DD_EXTREME(link_, t, (*interval_)(t).get(Real()), Angle()) :
                   D_EXTREME(link_, t, (*interval_)(t).get(Real()), Angle());
            break;

        case NORMAL:
        default:
            return (*order_)(t).get(int()) ?
                   DD_NORMAL(link_, t, (*interval_)(t).get(Real()), Angle()) :
                   D_NORMAL(link_, t, (*interval_)(t).get(Real()), Angle());
            break;
        }
    } else if (type == type_vector) {
        switch ((*accuracy_)(t).get(int())) {
        case ROUGH:
            return (*order_)(t).get(int()) ?
                   DD_ROUGH(link_, t, (*interval_)(t).get(Real()), Vector()) :
                   D_ROUGH(link_, t, (*interval_)(t).get(Real()), Vector());
            break;

        case FINE:
            return (*order_)(t).get(int()) ?
                   DD_FINE(link_, t, (*interval_)(t).get(Real()), Vector()) :
                   D_FINE(link_, t, (*interval_)(t).get(Real()), Vector());
            break;

        case EXTREME:
            return (*order_)(t).get(int()) ?
                   DD_EXTREME(link_, t, (*interval_)(t).get(Real()), Vector()) :
                   D_EXTREME(link_, t, (*interval_)(t).get(Real()), Vector());
            break;

        case NORMAL:
        default:
            return (*order_)(t).get(int()) ?
                   DD_NORMAL(link_, t, (*interval_)(t).get(Real()), Vector()) :
                   D_NORMAL(link_, t, (*interval_)(t).get(Real()), Vector());
            break;
        }
    }

    return ValueBase();
}

bool
ValueNode_Derivative::check_type(Type &type)
{
    return
        type == type_real ||
        type == type_time ||
        type == type_angle ||
        type == type_vector;
}

bool
ValueNode_Derivative::set_link_vfunc(int i, ValueNode::Handle value)
{
    assert(i >= 0 && i < link_count());

    switch (i) {
    case 0:
        CHECK_TYPE_AND_SET_VALUE(link_,    get_type());

    case 1:
        CHECK_TYPE_AND_SET_VALUE(interval_, type_real);

    case 2:
        CHECK_TYPE_AND_SET_VALUE(accuracy_, type_integer);

    case 3:
        CHECK_TYPE_AND_SET_VALUE(order_, type_integer);
    }

    return false;
}

ValueNode::LooseHandle
ValueNode_Derivative::get_link_vfunc(int i)const
{
    assert(i >= 0 && i < link_count());

    switch (i) {
    case 0:
        return link_;

    case 1:
        return interval_;

    case 2:
        return accuracy_;

    case 3:
        return order_;

    default:
        return 0;
    }
}

LinkableValueNode::Vocab
ValueNode_Derivative::get_children_vocab_vfunc()const
{
    if (children_vocab.size()) {
        return children_vocab;
    }

    LinkableValueNode::Vocab ret;
    ret.push_back(ParamDesc(ValueBase(), "link")
                  .set_local_name(_("Link"))
                  .set_description(_("Value to calculate the derivative"))
                 );
    ret.push_back(ParamDesc(ValueBase(), "interval")
                  .set_local_name(_("Interval"))
                  .set_description(_("Interval of time to calculate the finite differences"))
                 );
    ret.push_back(ParamDesc(ValueBase(), "accuracy")
                  .set_local_name(_("Accuracy"))
                  .set_description(_("Accuracy of the derivative"))
                  .set_hint("enum")
                  .add_enum_value(ROUGH, "rough", _("Rough"))
                  .add_enum_value(NORMAL, "normal", _("Normal"))
                  .add_enum_value(FINE, "fine", _("Fine"))
                  .add_enum_value(EXTREME, "extreme", _("Extreme"))
                 );
    ret.push_back(ParamDesc(ValueBase(), "order")
                  .set_local_name(_("Order"))
                  .set_description(_("Order of the derivative"))
                  .set_hint("enum")
                  .add_enum_value(FIRST, "first", _("First Derivative"))
                  .add_enum_value(SECOND, "second", _("Second Derivative"))
                 );
    return ret;
}